Is “sleep on it” good advice?

“This provides support for what Mom and Dad have always advised,” says Spencer. “There is something to be gained from taking a night to sleep on it when you’re facing an important decision. We found that the fact that you slept makes your decisions better.”

This role of sleep in everyday life is accepted as common wisdom, but it hasn’t been well characterized by science until now, she adds. She and her colleagues believe this sleep benefit in making decisions may be due to changes in underlying emotional or cognitive processes. “Our guess is that this enhanced effect on decision-making is something that depends on rapid-eye-movement or REM sleep, which is the creative period of our sleep cycle,” the psychologist notes. Results are in the current early online issue of the Journal of Sleep Research.